The ideas attributed to T. H. Huxley in the passage suggest that he would most likely agree with which of the following statements
A．An animal's brain size has little bearing on its ability to master complex behaviors. B．An animal's appearance is often influenced by environmental requirements and physical capabilities. C．Animals within a given family group are unlikely to change their appearance dramatically over a period of time. D．The pterosaurs should be classified as birds, not reptiles.